So i just saw the new SB Galil arm brace on what i think is a sig 552 pistol. I have a sig 556 pistol that i want to use that arm brace on it but need to find out how t attach it to my lower. Can any of the Sig guys here help me out here? Hard to tell by the pictures and lack of info if this brace will slip over an ar buffer tube or if its a proprietary design.   I was going to use the ACE folding mechanism and AR arm brace but i think this one looks a hell of alot better and seeing it on the SIG makes me have to get one for mine.
Heres the complete setup i want to duplicate.

Heres the arm brace itself

SB tactical just answered my question. Those guys respond fast. The arm brace fits over a pistol buffer tube and comes with one installed. They recommended using the ACE folding adapter but i think im going to use the Hera folding stock unit. Ill put up pics of it when i get it built out.

Thats a 553 Swiss San pistol. I plan to use that on mine once they are available. I have the Shockwave blade on it now. Am using the Double Diamond side folding adapter on mine as it installs with the same pin as the Swiss folding stock.

SB said it should be out by end of next week. I saw the DDLES adapter but it wont work on my 556, i got to use the ACE block or something similiar. I do like the look of that folding adapter or the factory ones better though.